Hardened Mechanical Properties of Self Compacting Geopolymer Mortar

Abstract

The self-compacting geopolymer mortar (SCGM) is a new revolutionary concept in the construction industry. This study presents a summary of different influencing parameters that effect the compressive strength of SCGM. The test results showed that the water to geopolymer solid ratio (W/GPS), sodium hydroxide (NaOH) concentration, curing temperature, and curing rest period were the important parameters that had a significant impact compressive strength of SCGM. The increase in fly ash to sand ratio from 0.5 to 0.67 had a negative impact on the compressive strength of SCGM. The increase in curing temperature from 50°C to 80°C resulted in a continuous increase in the compressive strength of SCGM, however, its effect was much more significant at higher NaOH concentrations. Moreover, a contin-uous increase in the rest period before heat curing also had a negative impact on the compressive strength of SCGM. The increase in mixer speed resulted in an increase in compressive strength due to proper mixing of high viscosity SCGM paste. The 28 days compressive strength of more than 20 MPa with good flowability can be achieved for SCGM mix with W/GPS less than 0.349, NaOH molarity of 16 M, and cured at 50°C to 80°C without any rest period.